1. Field of the Invention
The present invention relates to a coil frame, and more particularly, to a coil frame capable of connecting with another coil frame.
2. Description of the Prior Art
As decreased price and increased quality of liquid crystal displays (LCD) becomes a market trend, LCD displays are now widely used in electronic devices, such as notebook computers, personal digital assistants (PDA), mobile phones, monitors, and flat-panel televisions. LCD displays are passive lighting type flat-panel displays, so they require backlight modules to supply light to the LCD displays.
Typically, light generating devices in backlight modules are cold cathode fluorescent lamps (CCFL), external electrode fluorescent lamps (EEFL), or light emitting diodes (LED). Based on the locations of light generating devices, backlight modules can be categorized into two kinds: direct lighting type backlight modules and edge lighting type backlight modules. In a direct lighting type backlight module, a light generating device is disposed immediately below a display panel, so direct lighting type backlight modules are appropriate for display panels with high brightness requirements or large sized display panels, for example, computer monitors or flat-panel televisions. In an edge lighting type backlight module, a light-generating device is disposed near lateral sides of a display panel, so volume and production costs of LCD displays can be greatly decreased. Therefore, edge lighting type backlight modules are appropriate for small sized electronic devices.
Large sized LCD displays usually utilize direct lighting type multiple tube systems, requiring multiple transformers to drive the tubes. Please refer to FIG. 1. FIG. 1 is a schematic view of a transformer 1 according to the prior art. The transformer 1 comprises a coil frame 10 and two E-shaped cores 11 and 12. The coil frame 10 comprises a primary sub-coil-frame 14 and a secondary sub-coil-frame 13. Metal coils are wound on the primary sub-coil-frame 14 and the secondary sub-coil-frame 13 to form a primary coil and a secondary coil respectively. When an electrical current is supplied to the primary coil 14, magnetism induced by the electrical current forms a closed loop by physical contact of the two E-shaped cores 11 and 12. The transformer 1 in FIG. 1, however, can drive only one tube. In other words, the number of transformers has to be increased in order to drive more than one tube. In such a case, volume and production costs of LCD displays is greatly increased.
Please refer to FIG. 2. FIG. 2 is a schematic view of a transformer 2 of the prior art. The transformer 2 comprises a coil frame 20 and two E-shaped cores 21 and 22. The coil frame 10 comprises a primary sub-coil-frame 24 and two secondary sub-coil-frames 23 and 25. Metal coils are wound on the primary sub-coil-frame 24 and the secondary sub-coil-frames 23 and 25 to form a primary coil and two secondary coils respectively. Unlike the transformer 1 in FIG. 1, the transformer 2 in FIG. 2 can drive two tubes simultaneously. Moreover, volume of the transformer 2 is far less than a combined volume of two transformers 1. The transformer 2 is restricted by the shape of its core, however, and is thus limited in application.